Cole, Mary, and David Herbert. “Eight New Species of Gulella Pfeiffer, 1856 from the South-East Coast of South Africa (Gastropoda: Streptaxidae)”. European Journal of Taxonomy 813, no. 1 (April 11, 2022): 1–32. Accessed April 24, 2026. https://ejt.sandbox.publicknowledgeproject.org/index.php/ejt/article/view/1729.